Quantitative analysis of anthocyanins in natural fruit juices and evidence-based rationale for their inclusion as bioactive agents in individuals with increased physical activity

For the last few decades, plant bioactive molecules in various formulations, such as herbal medicines or dietary supplements, have been increasingly recommended for enhancing overall psycho-physical performance and resilience. The focus is directed towards natural sources of antioxidants, which not only provide health protection but also contribute to enhancing physical performance, accelerating recovery, and reducing oxidative stress through sports nutrition. Supplementation with anthocyanins has been identified as a means to accelerate recovery following intense physical activity, reduce inflammatory processes, and modulate vascular function in both recreational and professional athletes. The main aim of this study was to perform quantitative analysis of anthocyanins in a few natural fruit juices, obtained from Punica granatum (pomegranate), Vaccinium myrtillus (bilberry), Vitis vinifera (grape), Sambucus nigra (elderberry), and Aronia melanocarpa (chokeberry), that were found locally in the region of North Macedonia. Additionally, several other parameters were evaluated, including pH, organic acid content, and Brix values, in order to serve as evidence for their rational use as nutritional and functional potential for targeted supplementation. The results indicated significant variations depending mainly on the type of fruit the juices were obtained from. Pomegranate and bilberry juices exhibited the lowest pH values (3.16 and 3.29, respectively), consistent with conditions favoring anthocyanin stability. Pomegranate and elderberry samples demonstrated the highest titratable acidity. Chokeberry juice recorded the highest Brix value (26.2 °Brix), reflecting elevated levels of soluble solids. Elderberry juice demonstrated the highest measured concentration of total anthocyanins (>3.20 mg/L) and the highest measured concentration of monomeric anthocyanins (>1,50 mg/L). These findings provide evidence that natural fruit juices rich in anthocyanins represent an easily accessible and nutritionally valuable alternative to synthetic supplements, particularly in the context of sports nutrition. Among the examined samples, elderberry juice appeared to be the most effective choice, supporting its potential application in functional and sports-related nutrition or dietary supplementation.